Liquid detergent compositions



United States Patent Ofiicc 3,021,284 Patented Feb. 13, 1962 This invention relates to liquid detergent compositions and more particularly to liquid detergent compositions containing inorganic salts and alkylated aryl sulfonates.

The use of the various water soluble salts of the alkylated benzene sulfonic acids wherein the alkyl group contains from 9 to 15 carbon atoms as synthetic detergents has become increasingly important in the past several years. Detergent manufacturers have long recognized, however, that not only may cost savings be realized but also improved detergent properties be obtained if these synthetic detergents are mixed with certain inorganic salts to produce what is known as built formulations. These built formulations are particularly useful for heavy duty requirements in cleaning heavily soiled cotton cloth materials but at the same time they may be employed in less severe uses such as dishwashing. The early built formulations consisted primarily of a mixture of solid inorganic chemicals with solid synthetic detergents to produce a built material in the form of a flake or powder.

These solid built formulations were found objectionable by the consumer primarily for two reasonsone reason being that they were not readily soluble either in cold or hot water and required an appreciable time to go into solution, and the second reason being that the dust which arose from these flakes or powders was often times extremely irritating and caused violent sneezing by anyone standing in the'vicinity of its use. The most obvious solution to this problem was to produce a liquid detergent which would be readily soluble in water and which would be free of any irritating dustiness.

In attempting to produce liquid built detergent formulations it was found that only rather small amounts of solids would go into solution with the result that the amount of active ingredients in the liquid detergent composition was rather small, generally less than about 20 percent by weight and usually 10 to 12 percent by Weight. While these formulations overcame the objectionable characteristics of solid formulations, they were expensive since it was necessary to ship dilute solutions, thus a large part of their cost was simply the cost of transporting water. Moreover, attempts to make built formulations in slurry form were unsuccessful since stratification and settling occurred giving a non-homogeneous mixture.

A method now has been found, however, whereby superior amounts of alkyl benzene sulfonates and inorganic builders may be contained in an aqueous solution to provide a heavy duty concentrated liquid detergent composition.

It is an object of this invention to provide a heavy duty concentrated liquid detergent composition.

It is a further object of this invention to provide a heavy duty concentrated liquid detergent composition consisting of a built formulation wherein superior quantities of inorganic salts and synthetic alkyl benzene sulfonates are contained in aqueous solution.

Further objects of this invention will be apparent from the description and claims that follow.

In accordance with this invention it has been found that if morpholine or its salt with oleic acid, commonly called morpholine oleate, is included in certain built detergent formulations superior quantities of the inorganic salts and alkylated benzene sulfonates will be retained in aqueous solution.

The heavy duty concentrated liquid detergent composition of this invention contains the following active ingredients in aqueous solution with the range of concentration of each ingredient being based on the total weight of the solution:

Trisodium phosphate 2.5-5.0 Sodium tripolyphosphate 0-2.5 Potassium tripolyphosphate 5.0-7.5 Alkyl benzene sulfonate 7.5-l5.0 Laurylethanolamide 2.5-7.5

These ingredients are soluble when 1.0 percent to 2.5 percent by weight of morpholine is included in the solution. It has been found that from 5.0 percent to 12.0 percent by weight of morpholine oleate may be used instead of the morpholine with equal success.

Instead of trisodium phosphate, tripotassium or triammonium phosphate may be utilized in the same quantities and instead of sodium tripolyphosphate, potassium tri polyphosphate or ammonium tripolyphosphate may be utilized so that all of the tripolyphosphate is the potassium or ammonium salt.

It has been found, however, because of the somewhat lower solubility of the sodium salt that it is not possible to use sodium tripolyphosphate instead of the potassium tripolyphosphate in the formulation set forth above. These tripolyphosphates have the general formula:

wherein the M represents either sodium, potassium or the ammonium group.

The alkyl benzene sulfonate portion of the formulation consists of a mixture of percent to 70 percent by weight of a water soluble salt of a mono-alkylated benzene sulfonic acid in which the alkyl group contains from 9 to. 15 carbon atoms and 5 percent to 30 percent by weight of a water soluble salt of xylene sulfonic acid or ethyl benzene sulfonic acid. The preferred salts are the sodium, potassium and ammonium salts of these sulfonic acids.

The alkylated benzene hydrocarbons which are sulfonated and neutralized to produce the sulfonates containing from 9 to 15 carbon atoms in the alkyl group may be produced by any one of a number of well known methods; for example, the alkylation may be accomplished by treating an excess of the benzene with a halogenated aliphatic hydrocarbon of 9 to 15 carbon atoms in the presence of a suitable alkylation catalyst of the Friedel-Crafts type, i.e. AlCl to obtain substantial yields of monoalkylated benzenes. These alkylated benzenes may also be produced by alkylating benzene with an alcohol or mono-olefiin of 9 to 15 carbon atoms using either sulfuric acid or a Friedel-Crafts catalyst as the case may be.

A further method for producing the alkylated benzene or mixture of alkylated benzenes having 9 to 15 carbon atoms in the alkyl group is to polymerize an olefin such as propylene, or a gas stream containing propylene, with an acid catalyst such as a supported phosphoric acid catalyst or boron trifluoride catalyst at elevated temperatures and pressures according to well known methods thereby obtaining a mixture of propylene polymers which are ractionated to produce polymers of from 9 to 15 carbon atoms or intermediate fractions of a narrower molecular weight range. The benzene is then alkylated with the propylene polymer fraction in the presence of a Friedel- Crafts catalyst or with a sulfuric acid catalyst to produce the alkylated benzene or mixture of alkylated benzenes.

The xylenes to be employed may be one or a mixture of the isomeric xylenes, all of which are commercially available or the xylenes may have admixed therewith nuances various proportions of ethyl benzene including the case where the only 8 carbon atom alkylated benzene is ethyl benzene.

' 'I he alkylated benzene having an alkyl group of from 9 .to 15 carbon atoms or a mixture of alkylated benzenes within this range may be mixed with percent to 30 percent by weight of xylene or the other 8 carbon atom alkylated benzene mixtures described heretofore. The entire mixture is then subjected to sulfonation with an agent such as sulfuric acid of 98 percent to 100 percent concentration preferably at temperatures of from 150 F. to 160 B. using about one volume of acid to one volume .of the 'alkylated benzene-xylene mixture. If desired the sulfonation may be carried out with 20 percent fuming sulfuric acid at slightly lower temperatures, i.e. 135 F. with about one part by weight of acid toa'oout one part by weight of hydrocarbon. After the sulfonation is completed the reaction mixture is diluted with a solvent such as benzene or hexane and the spent sulfuric acid is settled out leaving the alkylated benzene sulfonic acids in solution in the immiscible benzene layer. The benzene solution of sulfonic acids may be extracted with water or aqueous alcohol to dissolve and remove the sulfonic acids, the water or alcohol solution is separated from the benzene, neutralized with a suitable base such as aqueous sodium hydroxide and resulting sulfonate solution evaporated to remove water or alcohol. Alternatively, the benzene solution of sulfonic acids may be treated with an aqueous alcohol solution containing a basic reagent to neutralize the mixture to form two immiscible liquid phases. The phase comprising the alcohol solution of sulfonates is separated from the benzene and this sulfonate solution thereafter is washed with additional benzene to remove traces of unsulfonated material and finally heated to remove the alcohol, Water and traces of hydrocarbon solvent from the sulfonate. Instead of sulfonating the higher alkylated benzenes and the xylenes together, the higher alkylated benzenes may be separately sulfonated and the xylene hydrocarbons separately sulfonated and the resulting products mixed.

Although the preferred sulfonate is the sodium salt, instead of the sodium salt the potassium or ammonium salts or mixtures of these salts of the alkylated benzene sulfonic acids may be used. The triethanolamine salts of the higher alkylated benzenes sulfonic acids also may be used in the formulation of this invention.

The laurylethanolamide which functions as a sudsing agent is commercially available and therefore the description of its production is unnecessary. Morpholine and'morpholine oleate likewise are commercially available chemicals.

In order to prepare the'novel formulations of this:

invention the trisodium phosphate, sodium tripolyphosphate and the potassium tripolyphosphate salts are added to water with heating to approximately 180 F. to 190 F. until they are dissolved. At this temperature they will dissolve rather readily and thereafter the solution is cooled to about 100 F. and the alkyl benzene sulfonate is added. Following addition of the sulfonate the laurylethanolamide and the morpholine or morpholine oleate are added to the solution at a temperature of 100 F. or lower, i.e. ambient temperatures. Upon standing and cooling to room temperature a clear homogeneous solution is obtained. If desired, the amount of water originally employed may be somewhat less than the amount desired in the final product so that after the addition of all of the ingredients additional water may be added to adjust the concentration to that desired. After the phosphate salts have been put into solution the actual order of addi tion of the remaining ingredients may be varied from that set forth although the preferred order of addition is that given.

The examples which follow will serve to illustrate certain specific embodiments of the invention.

4 Example I Three aqueous compositions were prepared containing the following ingredients in Weight percent based on the total weight of the composition:

| A l B O Trisodium phosphate 5. 0 5. 0 5. 0 Sodium trlpolyphosphate 2. 5 2. 5 2. 5 Potassium tripolyphosphate 7. 5 7. 5 7. 5 Sodium alkyl benzene sulfonate 15.0 15.0 15. 0 Laurylethanolamide r 7. 5 7. 5 15.0 Morpholinc oleate 7. 5 0 0 1 percent by Weight sodium mono-alkyl bcnzenesulfonates wherein the alkyl group contains between 9 and 15 carbon atoms with the major portion containing from 10 to 12 carbon atoms and 20 percent by weight sodium xylene sulfonate. These sulfonates were prepared by the joint sult'onetion of the corresponding alkyl benzene fraction and commercial xylene which had a typical analysis in weight percentas follows:

ortho-xylem 24 meta-xylene 45 para-xylene l 8 ethyl hen one 19 other hydrocarbons. 4

Formulations B and C did not produce a clear homogeneous solution but instead separated into two phases. Formulation A, however, containing the morpholine oleate was a clear single phase homogeneous solution.

Example II A liquid detergent composition was prepared having the same ingredients in the same concentrations in aqueous solution as set forth in composition A of EX- ample I except that the morpholine oleate was replaced by 1.5 percent by weight of morpholine. A clear, homogeneous liquid detergent composition was obtained.

Example III Example IV A number of aqueous detergent compositions were prepared which were similar to those of Example III except that morpholine was employed instead of morpholine oleate. It was found that at concentrations below about one percent by weight and above about 2.5 percent by weight, phase separation occurred and non-homogeneous compositions were obtained.

Example V 7 An aqueous composition was prepared having the following ingredients in weight percent based on the total weight of the composition: a

Trisodium phosphate 5.0 Sodium tripolyphosphate 2.5 Potassium tripolyphosphate 7.5 Sodium alkyl benzene sulfonate 1 10.0 Triethanolamine alkyl benzene sulfonate 5.0 Laurylethanolamide 5.0 Morpholine 1.5

'lhe sodium alkyl benzene sulfonatehad the same composition as in Example I.

2 The triethanolamine alkyl benzene'sulfonate was prepared by neutral zing with triethanolamine the mono-alkyl benzene sulfonic acid fraction of Example I wherein the alkyl group contained from S to 15 carbon atoms with the major portion having from 10 M12 carbon atoms.

A clear, homogeneous solution was obtained.

Example VI There was prepared an aqueous solution having the same composition as that of Example V except that 6 weight percent instead of weight percent of methanolamine mono-alkyl benzene sulfonate was employed and 5 weight percent of morpholine oleate was substituted for the 1.5 weight percent of morpholine. As in Example V, a clear homogeneous solution was obtained.

Example VII An aqueous composition was prepared identical with that of composition A of Example I except that instead of including the low molecular weight xylene and ethyl benzene sulfonates in the sodium alkyl benzene sulfonate portion of the composition, 15 percent by weight of the higher molecular weight sulfonate was used, i.e. wherein the alkyl group contained from 9 to 15 carbon atoms with the major portion having from 10 to 12 carbon atoms. Phase separation occurred and a non-homogeneous composition resulted. This demonstrated the necessity of using the mixed high and low molecular weight sodium alkyl benzene sulfonates rather than the sodium alkyl benzene sulfonate wherein the alkyl group contained from 9 to 15 carbon atoms only.

Example VIII An aqueous composition was prepared having the following ingredient in weight percent based on the total weight of the composition:

Trisodium phosphate 5 Sodium tripolyphosphate 2.5 Potassium tripolyphosphate 7.5 Triethanolamine alkyl benzene sulfonate 1 15.0 Laurylethanolamine 7.5

Morpholine oleate 7.5

1 The same triethanolamine salt as that of Example V.

A clear, homogeneous solution was obtained demonstrating that because of the greater solubility of the triethanolamine sulfonate it may be substituted directly for the mixed sulfonates of composition A of Example I.

Example IX A series of aqueous compositions similar to those of the preceding examples were prepared using various concentrations of the inorganic salts. It was found that clear, homogeneous solutions were obtained when the inorganic salt content did not exceed weight percent and with that amount of salt, only the potassium salts could be employed. When, however, the less costly and less soluble sodium salts were employed, the upper limits set forth hereinbefore could not be exceeded.

The efficacy of composition A of Example I and of the compositions of Examples II, V, VI and VIII was measured by use of the Atlas Launderometer, in the manner described in Soap and Sanitary Chemicals, September 1948, page 42. This test procedure by S. Machlis and E. B. Michaels was modified by using cotton cloth in place of the glass fibre and maintaining a temperature of 120 F. during the washing cycle. A detergent concentration of 0.3 percent solids was employed in test comparisons.

A detailed description of the testing device is found in the Technical Manual and Year Book of the American Association of Textile Chemists and Colorists, for 1947- 1948, on page 98.

It was found that the detergencies of the clear, homogeneous solutions of this invention were comparable to those of a recognized commercial standard powdered Trisodium phosphate 2.5- 5.0 Sodium tripolyphosphate 0 2.5 Potassium tripolyphosphate 5.0 7.5 Alkyl benzene sulfonate 7.5-15.0 Laurylethanolamide 2.5- 7.5 Mo'rpholine 1.0- 2.5

wherein the alkyl benzene sulfonate consists of a mixture of 95 percent to percent by weight of a water soluble salt of a mono-alkylated benzene sulfonic acid in which the alkyl group contains from 9 to 15 carbon atoms and 5 percent to 30 percent by weight of a water soluble salt of at least one alkylated benzene sulfonic acid from the group consisting of the isomeric xylene sulfonic acids and ethyl benzene sulfonic acid.

2. The liquid detergent composition of claim 1 wherein the water-soluble salts of the alkyl benzene sulfonic acids are the sodium salts.

3. The liquid detergent composition of claim 1 wherein the alkyl benzene sulfonate is the triethanolamine salt of the mono-alkylated benzene sulfonic acids in which the alkyl group contains from 9 to 15 carbon atoms.

4. An improved heavy duty liquid detergent composition consisting essentially of an aqueous solution of the following ingredients in weight percent based on the total weight of the solution:

Trisodium phosphate 2.5- 5.0 Sodium tripolyphosphate O 2.5 Potassium tripolyphosphate 5.0- 7.5 Alkyl benzene sulfonate 7.5-45.0 Laurylethanolamide 2.5- 7.5 Morpholine oleate 5.0-12.0

wherein the alkyl benzene sulfonate consists of a mixture of percent to 70 percent by weight of a water soluble salt of a mono-alkylated benzene sulfonic acid in which the alkyl group contains from 9 to 15 carbon atoms and 5 percent to 30 percent by weight of a water soluble salt of an alkylated benzene sulfonic acid from the group consisting of xylene sulfonic acid and ethyl benzene sulfonic acid.

5. The liquid detergent composition of claim 4 wherein the water-soluble salts of the alkyl benzene sulfonic acids are the sodium salts.

6. The liquid detergent composition of claim 4 wherein the alkyl benzene sulfonate is the triethanolamine salt of the mono-alkylated benzene sulfonic acids in which the alkyl group contains from 9 to 15 carbon atoms.

References Cited in the file of this patent UNITED STATES PATENTS 2,418,909 Skinner Apr. 15, 1947 2,560,839 Ayo et a1 July 17, 1951 2,581,677 Machlis et a1 Jan. 8, 1952 2,607,740 Vitale et a1 Aug. 19, 1952 2,859,182 Carroll Nov. 4, 1958 2,877,185 Krumrei Mar. 10, 1959 

4. AN IMPROVED HEAVY DUTY LIQUID DETERGENT COMPOSITION CONSISTING ESSENTIALLY OF AN AQUEOUS SOLUTION OF THE FOLLOWING INGREDIENTS IN WEIGHT PERCENT BASED ON THE TOTAL WEIGHT OF THE SOLUTION: 